啰哩吧嗦
南极留给大家的印象就是无边的冰原和憨态可掬的企鹅，不过白垩纪时期的南极可能是一片雨林。白垩纪时代是地球上最后一个超级温暖的时期，在此期间南极的植被覆盖率很高，并且沼泽雨林星罗棋布，一片欣欣向荣的景象。
白垩纪的南极为什么会那么热？
克拉格斯博士通过建模表明，当时南极大约有四个月的极夜，这表示这四个月中完全没有光照，笼罩在一片黑暗之中，因此保证南极温暖的热量来自哪里？只有一个可能，即温室气体的浓度远高预期，那样产生的温室效应才有可能达到如此恐怖的程度，简单的说当时地球上根本就不存在并存，和没有两极冰盖！或者说没有常年冰封的冰盖！
如果感兴趣的话，baidu搜搜“九千万年前南极茂密雨林，因为板块漂移？德科学家发现改写教科书“。
VOA原文
Today we know Antarctica as an extreme environment containing ice and snow.
But new research provides evidence that the area was very different in the past.
The evidence was found inside a piece of Earth sediment collected by researchers from under the seafloor off the coast of Antarctica.
In the sediment, they found forest soil estimated to be about 90 million years old.
This would have been in the Cretaceous Period, when dinosaurs were the main land animals.
The sediment was removed by scientists on the research icebreaker RV Polarstern in the Amundsen Sea near the Pine Island Glacier.
Johann Klages is a geologist with the Alfred Wegener Institute's Helmholtz Center for Polar and Marine Research in Germany.
He was the lead writer of a study on the findings, published in the journal Nature.
He said the sediment was collected from a depth of about 30 meters below the ocean floor.
Klages said an examination showed that the material formed on land, not in the ocean.
The researchers estimate that the area – about 900 kilometers from the South Pole – had average yearly temperatures of about 12 to 13 degrees Celsius.
During the warmest summer months, average temperatures likely reached between 20 to 25 degrees Celsius.
The average yearly temperature in that area is about 40 degrees below zero Celsius.
The examination process included the use of X-ray imaging technology.
Those results showed "a dense network of roots that spread through the entire soil layer," the Helmholtz Center said in a statement.
The condition of the soil was in such good condition that the researchers could see individual cell structures.
The dark brownish-gray soil included fine dirt particle sand hard clay, as well as substances linked to at least 65 different kinds of plants, the study found.
"If you would go to a forest near you and drill a hole, it would probably look pretty similar," Klages told the Reuters news agency.
He added that the plants included trees, ferns and flowering plants.
While no animal remains were found, Klages said there were likely dinosaurs, flying reptiles and many insects in the environment.
The research represents new evidence of the major climate changes Earth has experienced in the past - and is currently undergoing today.
The soil dates back to the planet's warmest period of the past 140 million years, with sea levels about 170 meters higher than today.
The researchers said that the rainforest environment in Antarctica was especially surprising because each year, the area experiences a four-month polar night when there is no sunlight to fuel plant life.
Klages said no ice sheets were present during the time, but seasonal snowfall was likely.
满满de知识点
Antarctica
美 [ænˈtɑːrktɪkə]
n. 南极洲
Sediment
美 [ˈsedɪmənt]
n. 沉积；沉淀物
Cretaceous 美 [krɪˈteɪʃəs]Period 白垩纪
Celsius
美 [ˈselsiəs]
n. 摄氏度
fine dirt particles and hard clay
细小的泥土颗粒和坚硬的粘土
fine
adj. 细小的
drill 美 [drɪl] a hole
钻一个洞
Reptile
美 [ˈreptaɪl,ˈreptl]
n. 爬行动物；
date back to
追溯到
参考译文
今天，我们知道南极洲是一个冰雪覆盖的极端环境。但新的研究提供了证据，表明该地区在过去是非常不同的。研究人员在南极洲海底下收集到的一块泥土沉积物中发现了这一证据。在沉积物中，他们发现大约有9000万年历史的森林土壤。这可能是在白垩纪，那时恐龙是主要的陆地动物。极星号破冰船上的科学家们在松岛冰川附近的阿蒙森海钻取了这些沉积物。约翰·克拉格斯(JohannKlages)是德国阿尔弗雷德·韦格纳研究所(AlfredWegener Institute)赫姆霍兹极地和海洋研究中心(HelmholtzCenter for Polar and Marine Research)的地质学家。他是这项研究的主要作者。该研究发表在《自然》(Nature)杂志上。他说，这些沉积物是从海床以下约30米深处收集的。克拉格斯说，检测证实，这些物质是在陆地上形成的，而不是在海洋中。研究人员估计，该地区距离南极约900公里，年平均气温约为12至13摄氏度。在夏季最热的几个月里，平均气温可能达到20到25摄氏度。这个地区目前年平均气温大约是摄氏零下40度。检查过程包括使用x射线成像技术。赫姆霍尔兹研究中心在一份声明中表示，研究结果表明“密集的根系网络遍布整个土层”。该土壤状况非常良好，研究人员可以看清单个细胞结构。研究发现，深棕灰色的土壤中含有细小的泥土颗粒和硬质粘土，以及至少与65种不同植物有关的物质。克拉格斯告诉路透社:“如果你到附近的森林里钻一个洞，它可能看起来非常相似。”他补充说，这些植物包括树木、蕨类植物和开花植物。虽然没有发现动物遗骸，但克拉格斯说，该生态环境中可能有恐龙、会飞的爬行动物和许多昆虫。这项研究提出了新的证据，证实地球过去经历过重大气候变化，并且目前仍在进行中。这些土壤可以追溯到地球过去1.4亿年来最温暖的时期，当时的海平面比现在高出约170米。研究人员表示，南极洲的热带雨林环境尤其令人惊讶，因为该地区每年都会经历长达四个月的极夜，在此期间没有阳光为植物生长提供能量。克拉格斯表示，这段时期该地区没有冰盖的存在，但可能会有季节性降雪。
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